What Causes Headaches And An Indentation On The Forehead After An Injury?

Hi I hit my head really hard 1.5 years ago and had a huge lump above my left eye. I didn t lose consciousness or throw up but had a very bad headache for days. After a few days the blood came down and I got a black eye and bruising spread across the left upper corner of my face. I was very worried and went to the hospital where they gave me a CT scan. They told me it was ok, no fracture or anything just a lot of bleeding under the skin because it was my scalp and I hit it so hard. The bruising went away eventually and I just carried on as usual. However, now I ve noticed the left side of me forehead looks different to the right, there s a couple of scars and the area of left temple beside my eye is depressed, it s quite a large pressed in area. This area is sore to touch still and I still get headaches there sometimes. Is this normal? Is the dent due to tissue loss from the large bruise? Will it ever fill out and the headaches stop? Thanks.